1. Filed of the Invention
The present invention relates to a selective complex of a lipoprotein with hemoglobin or a hemoglobin analogue; a method of assaying hemoglobin or a hemoglobin analogue in a sample, using the selective complex, and a kit for assaying hemoglobin or a hemoglobin analogue, using the selective complex in clinical examinations.
2. Discussion of the Background Art
In clinical examinations, it is required to selectively assay a target substance from a sample containing various coexisting substances. Accordingly, there have been employed a number of substances that specifically binds to target substances to form a pair just like a key and a keyhole, for example, antigen (including hapten)-antibody, ligand-receptor, substrate-enzyme, inhibitor-enzyme, or the like.
For example, the sandwich method is an immunoassay method using antibodies which is frequently employed. In this method, an antigen to be assayed is sandwiched between two kinds of antibodies. One of these antibodies is immobilized on a solid phase for capturing the antigen, while the other antibody is labeled. Then, the antigen to be assayed is allowed to react with the antibodies to thereby form a sandwich complex of immobilized antibody-antigen-labeled antibody. After removing the unreacted labeled antibody, the amount of the antigen is determined by measuring the label.
However, it generally takes much labor and costs a great deal to construct these antibodies, receptors, enzymes, and the like. In addition, some of them contain hardly available materials.
In clinical examinations relating to hemoglobin or hemoglobin analogues, the situation is similar. That is to say, substances having a specific affinity for hemoglobin (for example, haptoglobin) suffer from problems in cost and stable supply.